Bucking bar



May 11, 1943. E. B. LEAR 2,319,003

I aucxme BAR Fil ed Sept. 26, 1941 7 I8 26 /a I (3 4 27 /2 INVENTOR EARL 8. LEA/e ATTORNEY Patented May 11, 1943 UNITED STATES v PATENT OFFICE 2,319,003 7 I v BUCKING BAR Earl B. Lear, Garfield Heights, Ohio, assignor to The Cleveland Pneumatic Tool Company, Cleveland, Ohio. a corporation of Ohio Application September 26, 1941, Serial No. 412,483 4Claims. c1.

This invention relates broadly to riveting de-. vices and particularly to an-improved bucking bar assembly for use in conjunction therewith; One. object of this invention-is to. produce an improved bucking bar which may be inserted within otherwise inaccessible interiors of hollow structures such as tubes to facilitate the riveting thereof.

Another object of this invention is to produce an improved bucking bar which will reduce to a minimum the eiIort required to locate and hold it against a rivet during the upsetting thereof.

Another object of this invention is to produce an improved bucking bar capable of applying high pressure to a rivet end with relatively little pressure exerted by the operator.

Other objects and advantages more or less ancillary to the foregoing reside in the specific construction and aggroupment of the elements peculiar to this structure, as will become apparent from a more complete examination of this invention.

In the drawing:

Fig. 1 is a longitudinal sectional view of an improved bucking bar within two tubular members about to be riveted. Also shown in this figure is the front end of a riveting hammer applied on the rivet adapted to be backed up by the improved bucking bar.

Fig. 2 is a view similar to Fig. 1 but illustrating parts of the improved bucking bar in another position.

Fig. 3 is a longitudinal sectional view taken in a plane indicated by line 3-3 in Fig. 1.

Fig. 4 is a cross sectional view taken in a plane indicated by line 44 in Fig. 1.

Referring to the drawing, for purposes of lllustration, there are shown two tubular members It and II, the member H being formed with a reduced portion l2 fitted within the member In and adapted to be riveted thereto. In Fig. 1 a rivet I3 is shown to extend radially through members l0 and I2, which;rivet is engaged by a rivet set l4 slidably mounted within the front end I! of a regular riveting hammer which, as is wellknown in this art, has a reciprocable hammer l6 delivering impacts in rapid succession to the rivet set l4 for upsetting the rivet I3.

Referring now more particularly to the invention, the improved bucking bar includes a. substantially rectangular block or casing l1 adapted to be inserted into the tubular members intended to be riveted. The block I! is provided with a slot l8 extending vertically from one to the other end of the block and longitudinally a predetermined depth to form at the bottom thereof a partly cylindrical vertical guideway 19 in which is free to slide a plunger or bucking bar 20. In order to limit downward movement of the plunger relative tolthe block I], theguideway I9 is provided with a bottom wall 2! on which normally rests the plunger 20.

Intermediate its ends, the bucking bar 20 is provided with a partly cylindrical recess 22 ex tending laterally thereof and adapted to pivotally receive the rounded end 23 of a lever 24, which extends into the slot [8 of the casing I! where it is pivotally connected by a cross pin 25. In practice the lever 24 is made long enough to extend outside of the tubular member II) where it is accessible to the operator. In order to clear the upset ends of other rivets 26 in Fig. 1, the slot 18 of the casing I! may extend below the bottom 2| of the guideway 19, as at 21.

In the operation when the rivet I3 is about to be upset, the bucking bar assembly may be positioned into the tube III as shown in Fig. 1 and downward pressure applied on the lever 24 by the operator, thus causing upward movement of the plunger 20 toward the rivet l3. Impacts delivered by the riveting hammer IS on the rivet [3 will of course cause its free end to be gradually upset against the bucking bar in the usual manner until it finally reaches the final shape shown in Fig. 2. In operative position, the block l1 rests firmly on the bottom of the tube It or more specifically on the bottom of the extension I2 of the tube It while the plunger 20 is urged against the rivet l3 by relatively slight manual pressure exerted on the free end of the lever 24 protruding from the tube It. When the upsetting of the rivet I3 is completed, the bucking bar assembly may be removed from the tube It sufliciently to clear the already upset rivet 26 and then again be positioned for engagement with the next rivet intended to be upset.

From the foregoing, it will be understood that the simple and compact improved bucking bar above described will make it possible to reach rivets in cases heretofore inaccessible by the usual bucking bar and that through the lever 24 pressure against the rivet may be materially increased without fatigue to the operator.

Although the foregoing description is necessarily of a detailed character, in order to completely set forth the invention, it is to be understood that the specific terminology is not intended to be restrictive or confining and it is to be further understood that various rearrangeadapted to pivotally receive one end of said lever,

whereby the pivotal movement of said lever effects the slidable movement of said plunger into engagement with a rivet being set.

2. A device for holding rivets while riveting comprising, a block, a plunger slidable in said block for engagement with a rivet, a lever pivoted intermediate its ends to said block, one end of said lever having a rounded surface, and a semicylindrical shaped recess formed intermediate the ends of said plunger adapted to pivotally receive the rounded end of said lever, whereby the pivotal. movement of said lever efiects the slidable-movement of said plunger into engagement with a rivet being set.

3, A device for holding rivets While riveting comprising, a block, said block being formed with a slot extending vertically from one end to the other and longitudinally a predetermined depth to form a vertical cylindrical guideway, a plunger slidable in said guideway, a lever pivotally connected within said slot, and connecting means between said plunger and lever, whereby the pivotal movement of the lever in one direction efiects the slidable movement of said plunger into engagement with a rivet being set.

4. A device for holding rivets while riveting comprising, a substantially rectangular shaped block, said block being formed with a slot extending vertically from one end to the other and longitudinally a predetermined depth to form a vertical cylindrical guideway, a plunger slidable in said guideway, a lever pivotally connected within said slot, one end of said lever having a rounded surface, and a semi-cylindrical shaped recess formed intermediate the ends of said plunger adapted to pivotally receive the rounded end of said lever, whereby the pivotal movement of said lever efiects the slidable movement of said plunger into engagement with a rivet being set.

EARL B. LEAR. 

